Folding knife



FIG. 1 is a perspective view of the folding knife;

FIG. 2 is a front elevation view thereof;

FIG. 3 is a rear elevation view thereof;

FIG. 4 is a right elevation view thereof;

FIG. 5 is a left elevation view thereof;

FIG. 6 is a top plan view thereof;

FIG. 7 is bottom plan view thereof; and,

FIG. 8 is a perspective view of the folding knife in a closed position.

The broken lines depict portions of the folding knife in which the design is embodied that are not considered part of the claimed design. 

CLAIM The ornamental design for a folding knife, as shown and described. 